Normally, products are held ready for sale in retail shops or similar establishments, selected by the purchaser and then distributed in return for payment of them. This means that all products which are planned to be sold must be stored and held available in shops which are equipped at great expense. Since storage space and sales space are in short supply and are expensive, this represents a problem because of the large storage space which is required for the products. A further problem of known retail shops consists in the fact that they make it necessary that a purchaser himself goes to the site where the shop is located in order to select and purchase the products which are desired by him. This means that purchasers drive in their cars to the retail shops in order to be able to transport the products which have been purchased. Traffic jams in the downtown area, especially on certain days when products are sold (in Germany, for example, on Thursday evenings and Saturdays when shops are open for sales) are the consequence.